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Dear WIEN users,<br>
If the gaps are not correct with the three options in the program;
then in the case of several bands the bandedges should not be very
precise. Is that correct? <br>
For example, in MgB2 there are four bands at Ef, but two of them
have the upper edge at ~0.8eV is this value correct?<br>
Is the GGA option 25 stil available and would it give the correct
values for these cases?<br>
Yours<br>
<br>
Pablo de la Mora<br>
-------------------------------------------<br>
Peter Blaha wrote:
<blockquote
cite="midPine.LNX.4.33.0203201405570.4741-100000@susi.theochem.tuwien.ac.at"
type="cite">
<pre wrap="">====
Peter Blaha <a class="moz-txt-link-rfc2396E" href="mailto:pblaha@theochem.tuwien.ac.at"><pblaha@theochem.tuwien.ac.at></a>
submitted the following contribution:
====
</pre>
<blockquote type="cite">
<pre wrap="">I make calculations of AlN,GaN and InN in wurtzite structure using
WIEN97.10
The bandgaps for AlN y GaN are 50% below of the experimental value, but
the bandgap for InN is zero.
</pre>
</blockquote>
<pre wrap=""><!---->
This is what LDA or the common GGAs give.
</pre>
<blockquote type="cite">
<pre wrap="">How I can make calculations more precise of bandgaps in WIEN97.10?
</pre>
</blockquote>
<pre wrap=""><!---->
You can use GGA option 25. This is due to Engel and Vosko. It gives much
better bandgaps (often even pretty good), but you have to pay a price:
Never use the total energy! Equillibrium volumes,... are way too large.</pre>
</blockquote>
<br>
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